I realised this last weekend, when I played it for the first time in, y'know, forever. I think, like all of us, I'd been taking Space Invaders for granted for far too long. Its ubiquity as the spark which ignited the Golden Age of Gaming has overshadowed what a work of genius the game actually is.
Yes, it was a whole bundle of firsts, and it's important in all manner of ways, but there's a reason why it's Space Invaders and not, say, Gun Fight, that has endured. And that reason is this reason: like The Beatles, or The Sex Pistols, or Star Wars, or the iPhone... it was in and of itself brilliant; not just for the time, but for all time.
I've played so many old games that I remember fondly, and now I sort of come to expect them to be broken, straining at the restrictions of the hardware, or glitchy, or trying too hard to experiment, or just damned impossible.
Space Invaders, much to my surprise, isn't like that; it works as well now as it did then.